Electric vacuum cleaner

ABSTRACT

An electric vacuum cleaner comprises a vertical type cleaner body provided with a dust collection chamber a handle protrusively provided on an upper portion of the cleaner body, a suction nozzle provided on an lower portion of the cleaner body in such a manner as to communicate with the dust collection chamber being rotatable back and forth with respect to the cleaner body, and being contactable with a surface to be cleaned, an electric fan provided in the suction nozzle, and a rotary brush which is rotated by the electric fan and is built in the suction nozzle. A clutch mechanism which transmits and interrupts power to the rotary brush is provided between the rotary brush and the electric fan. The suction nozzle is rotatably provided on the cleaner body via a hinge mechanism. The clutch mechanism is coupled to the hinge mechanism by a link mechanism.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a vertical type electric vacuumcleaner, called an upright type or a stick type electric vacuum cleaner.

2. Description of the Related Art

Japanese Unexamined Patent Publication No. 2002-119449 discloses aconventional upright type vacuum cleaner of this type which comprises acleaner body, a dust collection chamber a fan motor, and a suctionnozzle pivotably supported at the bottom of the cleaner body. The dustcollection chamber and the fan motor are built in the cleaner body.Provided in the suction nozzle is a rotary brush structured in such away that the tips of flocked fabrics of the rotary brush slightlyprotrude from the surface of a bottom plate. A pulley is securely fittedover one end of the rotation shaft of the rotary brush. As the rotarybrush is rotated by a belt which is driven by the fan motor, the flockedfabrics scoop out the dust from a carpet, and the dust is collected inthe dust collection chamber through a hose.

In the conventional vacuum cleaner of the publication, however, as therotary brush is coupled to the fan motor by the belt, the rotary brushis constantly rotated while the electrical vacuum cleaner is operated.This raises the following problem. The electrical vacuum cleaner is usedwhile moving the cleaner body tilted to the suction nozzle so that whenthe cleaner body is set upright and the suction nozzle is allowed tocome at rest while the fan motor is in operation, as in a case where,for example, cleaning is temporary suspended, the same portion of asurface to be cleaned like the carpet is continuously rubbed by therotary brush continuously rotating, and the continuously rubbed portionof the carpet or the like is likely to be damaged.

The object of the invention is to prevent a damage on a surface to becleaned by stopping a rotary brush with a suction nozzle being at restin an electric vacuum cleaner having the rotary brush provided at thesuction nozzle.

SUMMARY OF THE INVENTION

An electric vacuum cleaner according to the first aspect of theinvention comprises a vertical type cleaner body provided with a dustcollection chamber a handle protrusively provided on the upper portionof the cleaner body, a suction nozzle provided on the lower portion ofthe cleaner body in such a manner as to communicate with the dustcollection chamber being rotatable back and forth with respect to thecleaner body, and being contactable with a surface to be cleaned, anelectric fan having a motor and provided in the suction nozzle, a rotarybrush which is rotated by the motor of the electric fan, and is built inthe suction nozzle, and a clutch mechanism which is provided between therotary brush and the electric fan, and transmits and interrupts power tothe rotary brush.

The suction nozzle may be rotatably provided on the cleaner body via ahinge mechanism, and the clutch mechanism is coupled to the hingemechanism by a link mechanism.

The electric vacuum cleaner may further comprise a pulley which isprovided on the driving side of the clutch mechanism, a first belt whichis stretched over the pulley and the output shaft of the electric fan, afollower gear which is provided on the follower side of the clutchmechanism, and a second belt which is stretched over the follower gearand the rotary brush.

There may be a pair of the rotary brushes, each having a coaxialinterlocking gear, and a third belt which is stretched over theinterlocking gears.

The link mechanism may comprise a first joint member engaged with thehinge mechanism, a second joint member engaged with the clutchmechanism, and a link which links the first joint member to the secondjoint member.

The link may comprise a tabular member formed in an approximately Lshape, and is axially supported to the suction nozzle by a pin.

The electric vacuum cleaner may further comprise a guide so provided inthe suction nozzle as to support the second joint member.

According to the first aspect of the invention, because the clutchmechanism transmits the power to the rotary brush from the electric fan,only when the suction nozzle is moved back and forth to collect thedust, the rotary brush is to rotate, and when the suction nozzle isallowed to be at rest, the rotary brush is stopped. This makes itpossible to prevent a damage on the surface to be cleaned like a carpet.

BRIEF DESCRIPTION OF THE DRAWINGS

The object, other objects, and advantages of the invention will be moreapparent upon reading of the following detailed description togetherwith the accompanying drawings in which:

FIG. 1 is a perspective view of an electric vacuum cleaner according toan embodiment of the invention;

FIG. 2 is a rear view of the electric vacuum cleaner according to theembodiment of the invention;

FIG. 3 is an exploded perspective view illustrating a suction nozzleaccording to the embodiment of the invention;

FIG. 4 is a perspective view illustrating a joint pipe according to theembodiment of the invention; and

FIGS. 5A and 5B are exploded perspective views illustrating essentialparts of the suction nozzle, FIG. 5A illustrating a cleaner body tilteddownwardly, FIG. 5B illustrating the cleaner body standing upright.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A preferred embodiment of the invention will now be explained withreference to the accompanying drawings. The embodiment explained belowis not limiting the scope of the invention as set forth in the attachedclaims. The invention need not have all of the components that will bediscussed below as the essential requirements in some cases.

As illustrated in FIG. 1, a bar-like handle 2 which protrudes upwardlyis provided on the upper portion of a cleaner body 1 of a vertical typeon whose lower portion a suction nozzle 4 which contacts a surface 3 tobe cleaned like a carpet is provided. The suction nozzle 4 is providedwith a suction port 11 on the front side of the bottom face of thatnozzle. The cleaner body 1 is provided in such a manner as to berotatable at least back and forth in relation to the suction nozzle 4via a hinge mechanism 5 provided on the rear portion of the suctionnozzle 4. Wheels 6 are provided on both right and left sides of thesuction nozzle 4. An electric fan 7 is built in the suction nozzle 4.The electric fan 7 comprises a motor 7A and a fan 7B which is directlyconnected to one end of an output shaft 34 of the motor 7A. The primaryside, S, of the electric fan 7 is communicated with the suction port 11through first and second air channels 22 and 23 both to be describedlater. The secondary side, E, of the electric fan 7 is communicated withan exhaust vent 8 in the top face of the suction nozzle 4.

A dust collection chamber 9 which extends in the vertical direction isdetachably provided on the front side of the cleaner body 1. The entiredust collection chamber 9 is formed of a transparent or semi-transparentsynthetic resin. Accordingly, the amount of dust collected in the dustcollection chamber 9 is visible from outside.

Provided on the upper portion of the front side of the cleaner body 1 isa vortex flow generation mechanism 10 which is detachable from thecleaner body 1. The vortex flow generation mechanism 10 fits into theupper aperture of the dust collection chamber 9 in such a way as to beable to block the upper aperture. The vortex flow generation mechanism10 so introduces the primary side of the airflow into the dustcollection chamber 9 as to guide the airflow along the innercircumferential surface of the dust collection chamber 9 to generate avortex flow and leads the generated vortex flow out of the dustcollection chamber 9, via a non-illustrated filter. The dust collectionchamber 9 is held in a suspended manner by the vortex flow generationmechanism 10.

The suction nozzle 4 has a lower case 4A with an approximatelyrectangular plane, and an upper case 4B provided above the lower case 4Awith a space in between to house the electric fan 7, the rotary brushes12, and the like. The wheels 6 are provided on the right and left of therear side of the lower case 4A.

The hinge mechanism 5 which is provided on the center of the rear sideof the suction nozzle 4 is constituted by providing an approximatelyT-shaped joint pipe 13 on the rear portion of the suction nozzle 4. Thejoint pipe 13 is approximately symmetrically formed by providing anapproximately L-shaped first pipe section 13A integral with anapproximately L-shaped second pipe section 13B. The first pipe member13A further comprises a first lateral pipe section 14 and a firstvertical pipe section 16. The first lateral pipe section 14 and thefirst vertical pipe section 16 intersect with each other atapproximately the right angles, and their interiors communicate witheach other. The second pipe member 13B further comprises a secondlateral pipe section 15 and a second vertical pipe section 17. Thesecond lateral pipe section 15 and the second vertical pipe section 17intersect with each other at approximately the right angles, and theirinteriors communicate with each other, as per the first pipe member 13A.The first lateral pipe section 14 and the second lateral pipe section 15are provided side by side so as to be approximately coaxial along theaxial center X in the right and left direction. The first vertical pipesection 16 and the second vertical pipe section 17 are formed integralwith each other adjoining each other side by side with their axes (notillustrated) being in parallel with each other. The integral andside-by-side formation of both vertical pipe sections 16 and 17 providesa connection section 13C above the joint pipe 13. A flange like stopper18 is formed on the outer circumference of the lower-portion side of theconnection section 13C.

A pair of bearings 19 are provided on the rear side of the suctionnozzle 4. The bearings 19 are provided on the right and left of theaxial center X. One bearing 19 receives the first lateral pipe section14 so that the first lateral pipe section 14 rotatably pivots. Likewise,the other bearing 19 receives the second lateral pipe section 15 so thatthe second lateral pipe section 15 rotatably pivots. Each of thebearings 19 is constituted by combining halved pieces respectivelyformed on the lower case 4A and the upper case 4B. The bearings 19rotatably support flange portions 14A and 15A with large diameters,respectively. The flange portions 14A and 15A are provided on the firstlateral section 14 and the second lateral section 15, respectively. Thepivotable support of the first lateral pipe section 14 and secondlateral pipe section 15 of the joint pipe 13 by the pair of bearings 19provides the hinge mechanism 5.

Provided on the lower end of the cleaner body 1 are a first connectionpipe 20 which is connected and communicated with the first vertical pipesection 16, and a second connection pipe 21 which is connected andcommunicated with the second vertical pipe 17. The first connection pipe20 and the second connection pipe 21 are so provided in the cleaner body1 as to be laterally arranged side by side. The first and secondconnection pipes 20 and 21 are each formed in a pipe-like shape, but maybe formed integral with each other. Alternatively, the first and secondconnection pipes 20 and 21 may be integrated with the cleaner body 1, orformed in such a manner as to define a single assembly with the cleanerbody 1.

The first air channel 22 runs from the suction port 11 to the dustcollection chamber 9 through the first pipe section 13A of the jointpipe 13, the second air channel 23 runs from the dust collection chamber9 to the primary side S of the electric fan 7 through the second pipesection 13B of the joint pipe 13, and a third air channel 24 runs fromthe secondary side E of the electric fan 7 to the exhaust vent 8provided in the upper case 4B.

The first air channel 22 is for suction from the suction nozzle 4 to thedust collection chamber 9. The first air channel 22 runs from thesuction port 11 to the first lateral pipe section 14 through an innerpassage 25 provided in the suction nozzle 4 and extending back andforth, and runs from the first vertical pipe section 16 to the vortexflow generation mechanism 10 and the dust collection chamber 9 throughthe first connection pipe 20, connected to the first vertical pipesection 16, and a flexible pipe 26 located outside the cleaner body 1.Detachment of the leading end of the flexible pipe 26 from the firstconnection pipe 20 makes it possible to directly collect the dust fromthe flexible pipe 26.

The second air channel 23 is for suction from the dust collectionchamber 9 to the electric fan 7. The second air channel 23 runs from thesecondary side of the dust collection chamber 9 to the second verticalpipe section 17 connected to the second connection pipe 21 inside thecleaner body 1, through the second connection pipe 21 and reaches theprimary side S of the electric fan 7 through the second lateral pipesection 15, and an intermediate pipe 27 which runs from the secondlateral pipe section 15 to the primary side S of the electric fan 7. Theintermediate pipe 27 passes under the electric fan 7 and communicates anoutlet 27A to the primary side S of the electric fan 7.

The third air channel 24 is for exhaust, running from the secondary sideE of the electric fan 7 to the exhaust vent 8.

Meanwhile, an unlock button 28 unlocks a lock device (not illustrated)which locks the connection section 13C to the cleaner body 1.

As illustrated in FIGS. 3, 5A, and 5B, the suction port 11 is formed inthe front side of the lower case 4A, and the pair of rotary brushes 12whose rotation axes extend in the right and left direction are soarranged on the front and rear sides of the suction port 11 as to beapproximately in parallel to each other. The electric fan 7 is disposedat the approximate center of the suction nozzle 4.

The rotary brushes 12 are so structured as to be rotated by drivingforce transmitted from the motor 7A through a power transmission device30. The power transmission device 30 comprises a clutch mechanism 32which transmits and interrupts driving force, a pulley 33 which isprovided on the driving side of the clutch mechanism 32, a first belt 35which is stretched over the pulley 33 and the output shaft 34 of themotor 7A, a follower gear 36 which is provided on the follower side ofthe clutch mechanism 32, and a second belt 37 which is stretched overthe follower gear 36 and the rotary brush 12. The clutch mechanism 32mechanically connects and disconnects the pulley 33 and the followergear 36. The clutch mechanism 32 initially disconnects the pulley 33from the follower gear 36.

Each rotary brush 12 has coaxial interlocking gears 38, and supportpieces 39 respectively provided on both ends of the rotary brush 12. Thesupport pieces 39 are provided outside the interlocking gears 38. Thesupport pieces 39 of the pair of rotary brushes 12 are respectivelyinserted into support frames 40 formed on the bottom case 4A, thusrotatably supporting the pair of brushes to the bottom case 4A. A thirdbelt 41 stretches over the interlocking gear 38 at the opposite end ofthe driving rotary brush 12A, disposed on the rear side of the suctionport 11, to the second belt 37, and the interlocking gear 38 at theopposite end of the follower rotary brush 12B, disposed on the frontside of the suction port 11, to the second belt 37, so that both brushes12A, 12B rotate in conjunction with each other.

The clutch mechanism 32 is coupled to the hinge mechanism 5 by a linkmechanism 42. The link mechanism 42 comprises an engagement member 43protruding from the outer circumference of the first lateral pipesection 14, a first joint member 44 engaged with the engagement member43, a second joint member 45 engaged with the clutch mechanism 32, alink 46 which links the first joint member 44 to the second joint member45, and a pin 48 which axially supports the link 46 to the bottom case4A.

The engagement member 43 is constituted by a tabular claw member soformed as to protrude in the direction orthogonal to the axial center Xin the figure, and is provided at a position opposite to the first jointmember 44.

One end of the first joint member 44 is provided with a groove-likeengagement-reception portion 44A engaged with the engagement member 43,and the other end of the first joint member 44 is axially supported bythe link 46. Accordingly, as the engagement member 43 rotates, the firstjoint member 44 moves in the backward and forward direction of thesuction nozzle 4 in response to the rotation of the engagement member43.

One end 45A of the second joint member 45 is coupled to the clutchmechanism 32, and the other end 45B of the second joint member 45 isaxially supported by the link 46. The second joint member 46 is slidablysupported by a guide 47 formed on the lower case 4A. Accordingly, as thesecond joint member 45 moves rightward or leftward of the suction nozzle4, the clutch mechanism 32 connects or disconnects the pulley 33 and thefollower gear 36 in response to the movement of the second joint member45. The second joint member 45 has an urging member 50 for urging thesecond joint member 45 toward the clutch mechanism 32, and the urgingmember 50 allows the clutch mechanism 32 to connect the pulley 33 to thefollower gear 36.

The link 46 is constituted by an approximately L-shaped tabular member.The approximate center of the link 46 is axially supported to the lowercase 4A by the pin 48. The other end 44B of the first joint member 44and the other end 45B of the second joint member 45 are respectivelysupported on one side of the link 46 and the other side thereof in arotatable manner. The link 46 transforms the backward and forward motionof the first joint member 44 inside the suction nozzle 4 into therightward and leftward motion of the second joint member 45 inside thesuction nozzle 4.

Next, an operation of the above-described structure will be explained.First, a user connects the cleaner body 1 to the suction nozzle 4beforehand. In this connection work, the first vertical pipe section 16is inserted into the first connection pipe 20, and the second verticalpipe section 17 is simultaneously inserted into the second connectionpipe 21. At this time, the first connection pipe 20 and the secondconnection pipe 21 contact the stopper 18, thus aligned in the up anddown directions, and the lock mechanism (not illustrated) automaticallylocks the connection between the cleaner body 1 and the suction nozzle4. This lock is released by manipulation of the unlock bottom 28provided on the rear face of the cleaner body 1.

In vacuuming, the user grabs the handle 2, starts up the electric fan 7,puts the suction nozzle 4 on the surface 3 to be cleaned, tilts thecleaner body 1 backwardly around the hinge mechanism 5, and moves theelectric vacuum cleaner back and forth in that condition. At the time ofbackward and forward movement, as both of the first and second lateralpipe sections 14, 15 of the joint pipe 13 are pivotably supported by thebearings 19 and those pipe sections can coaxially rotate, the cleanerbody 1 and the handle 2 can be freely tilted relative to the suctionnozzle 4.

An explanation will now be given of an operation in a case wherevacuuming is carried out, that is, where the cleaner body 1 is tiltedbackward of the suction nozzle 4. First, as the cleaner body 1 standingupright to the suction nozzle 4 is tilted backwardly, the engagementmember 43 formed in such a manner as to define a single assembly withthe first lateral pipe section 14 rotates in the forward direction, andmoves forwardly. The forward movement of the engagement member 43releases the engagement between the engagement-reception section 44A ofthe first joint member 44 and the engagement member 43. When theengagement between the engagement member 43 and the first joint member44 is released, the second joint member 45 is moved toward the left asviewed from the front, that is, the direction toward the clutchmechanism 32 by the urging force of the urging member 50, thus engagingthe clutch mechanism 32, and the first joint member 44 moves forwardlyin the suction nozzle 4 via the link 46 which rotates clockwise aroundthe pin 48 as viewed from the above. As the second joint member 45 movestoward the clutch mechanism 32 to engage the clutch mechanism 32, thepulley 33 and the follower gear 36 are connected to each other, drivingforce of the motor 7A is transmitted to the driving rotary brush 12Athrough the first and second belts 35, 37. As the driving force istransmitted to the driving rotary brush 12A, the follower rotary brush12B interlocks with the driving rotary brush 12A via the third belt 41provided on the one end opposite to the second belt 37, and rotates inthe same direction as that of the driving rotary brush 12A. As describedabove, in a case where the cleaner body 1 is tilted backward of thesuction nozzle 4, the driving force is surely transmitted to the rotarybrushes 12 from the motor 7A through the clutch mechanism 32 to rotatethe rotary brushes 12, and this makes it possible to efficiently collectthe dust.

Next, an explanation will be given of a case where dust collection isnot carried out, that is, where the cleaner body 1 tilted backward ofthe suction nozzle 4 is allowed to stand upright for, for example,temporary suspending cleaning. As the cleaner body 1 tilted backwardlyis rotated around the hinge mechanism 5 so as to allow the cleaner body1 to stand upright relative to the suction nozzle 4, the engagementmember 43 formed in such a manner as to define a single assembly withthe first lateral pipe section 14 rotates in the reverse direction, andmoves backwardly. When moving backwardly, the engagement member 43re-engages with the engagement-reception section 44A of the first jointmember 44, and the first joint member 44 is pulled by the engagementmember 43, thereby moving backwardly in the suction nozzle 4. As thefirst joint member 44 moves backwardly in the suction nozzle 4, thesecond joint member 45 moves toward the right as viewed from the front,that is, moves in such a direction as to be away from the clutchmechanism 32 via the link 46 which rotates counterclockwise around thepin 48 as viewed from the above. As the second joint member 45 moves insuch a direction as to be away from the clutch mechanism 32, thefollower gear 36 is separated from the pulley 33 in the clutch mechanism32. Separating the follower gear 36 from the pulley 33 makes thefollower gear 36 idle, and the rotary brushes 12 are stopped. Asexplained above, in a case where the cleaner body 1 is allowed to standupright relative to the suction nozzle 4, that is, where the electricfan 7 is in operation, but the user does not want to do dust collectionsuch that cleaning is temporary suspended, the clutch mechanism 32interrupts the transmission of the driving force from the motor 7A tothe rotary brushes 12, and the rotary brushes 12 does not continuouslyrotate with the suction nozzle 4 being at rest. Accordingly, continuousrubbing of only a certain area of the surface 3 to be cleaned whichcontacts the rotary brushes 12 is prevented, thereby preventing a damageon the certain area to be cleaned.

The dust on the surface 3 to be cleaned is sucked through the suctionport 11 together with the air, and reaches the vortex flow generationmechanism 10 via the first air channel 22. The vortex flow generationmechanism 10 introduces the airflow containing the dust into the dustcollection chamber 9 from the above, and generates a spiral vortex flowin the dust collection chamber 9 along the inner surface of the dustcollection chamber 9, separates the dust by centrifugal force at thedown-draft stage, and collects the dust on the bottom portion of thedust collection chamber 9. The clean airflow from which the dust iseliminated rises toward the central portion of the dust collectionchamber 9, and evacuates the airflow from above the dust collectionchamber 9, to the outside of the vortex flow generation mechanism 10.The evacuated airflow from the vortex flow generation mechanism 10passes through the second air channel 23, the electric fan 7, and thethird air channel 24, and is evacuated from the exhaust vent 8 out ofthe suction nozzle 4.

As explained above, according to the embodiment, the electric vacuumcleaner comprises the vertical type cleaner body 1 provided with thedust collection chamber 9, the handle 2 protrusively provided on theupper portion of the cleaner body 1, the suction nozzle 4 provided onthe lower portion of the cleaner body 1 in such a manner as tocommunicate with the dust collection chamber 9, be rotatable back andforth with respect to the cleaner body 1, and being contactable with thesurface 3 to be cleaned, the electric fan 7 provided in the suctionnozzle 4, the rotary brushes 12 which are rotated by the electric fan 7and are built in the suction nozzle 4, and the clutch mechanism 32 whichis provided between the rotary brushes 12 and the electric fan 7, andtransmits and interrupts power to the rotary brushes 12. Accordingly,only when the suction nozzle 4 is moved back and forth to collect thedust, power of the electric fan 7 is transmitted to the rotary brushes12 to rotate the rotary brushes 12, and when the dust collection is notcarried out and the suction nozzle 4 is allowed to be at rest, thetransmission of the power from the electric fan 7 toward the rotarybrushes 12 is interrupted, thereby stopping the rotary brushes 12. Thismakes it possible to prevent continuous rotations of the rotary brushes12 while contacting the certain area of the surface 3 to be cleaned,thereby preventing a damage on the certain area of the surface 3 to becleaned.

The suction nozzle 4 is rotatably provided on the cleaner body 1 via thehinge mechanism 5, and the clutch mechanism 32 is coupled to the hingemechanism 5 by the link mechanism 42. Accordingly, when the cleaner body1 is tilted backward of the suction nozzle 4 to move the suction nozzle4 back and forth, the rotary brushes 12 are rotated, and when thecleaner body 1 is allowed to stand upright for the purpose of, forexample, temporary suspending cleaning, the rotary brushes 12 arestopped. Therefore, it is possible to rotate the rotary brushes 12 onlywhen the suction nozzle 4 is moved back and forth in accordance with themotion of the cleaner body 1. It is also possible to interrupt thetransmission of the power from the electric fan 7 to the rotary brushes12 to stop the rotary brushes 12 when the suction nozzle 4 is allowed tobe at rest. This makes it possible to prevent continuous rotations ofthe rotary brushes 12 while contacting the certain area of the surface 3to be cleaned, thereby preventing a damage on the certain area of thesurface 3 to be cleaned.

1. An electric vacuum cleaner comprising: a vertical type cleaner bodyprovided with a dust collection chamber; a handle protrusively providedon an upper portion of said cleaner body; a suction nozzle provided onan lower portion of said cleaner body in such a manner as to communicatewith said dust collection chamber being rotatable back and forth withrespect to said cleaner body and being contactable with a surface to becleaned; an electric fan having a motor and provided in said suctionnozzle; a rotary brush which is rotated by said motor of said electricfan, and is built in said suction nozzle; and a clutch mechanism whichis provided between said rotary brush and said electric fan, andtransmits and interrupts power to said rotary brush.
 2. The electricvacuum cleaner according to claim 1, wherein said suction nozzle isrotatably provided on said cleaner body via a hinge mechanism, and saidclutch mechanism is coupled to said hinge mechanism by a link mechanism.3. The electric vacuum cleaner according to claim 1, further comprisinga pulley which is provided on a driving side of said clutch mechanism, afirst belt which is stretched over said pulley and an output shaft ofsaid electric fan, a follower gear which is provided on a follower sideof said clutch mechanism, and a second belt which is stretched over saidfollower gear and said rotary brush.
 4. The electric vacuum cleaneraccording to claim 3, wherein there are a pair of said rotary brushes,each having a coaxial interlocking gear, and a third belt which isstretched over said interlocking gears.
 5. The electric vacuum cleaneraccording to claim 2, wherein said link mechanism comprises a firstjoint member engaged with said hinge mechanism, a second joint memberengaged with said clutch mechanism, and a link which links said firstjoint member to said second joint member.
 6. The electric vacuum cleaneraccording to claim 5, wherein said link comprises a tabular memberformed in an approximately L shape, and is axially supported to saidsuction nozzle by a pin.
 7. The electric vacuum cleaner according toclaim 5, further comprising a guide so provided in said suction nozzleas to support said second joint member.